import { mkdirSync, writeFileSync, existsSync } from 'fs';
import { join, dirname } from 'path';
import { fileURLToPath } from 'url';

const __dirname = dirname(fileURLToPath(import.meta.url));
const outDir = join(__dirname, '..', 'public', 'thumbnails');
mkdirSync(outDir, { recursive: true });

// Favicon
const favicon = `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 32 32">
  <rect width="32" height="32" rx="6" fill="#d97706"/>
  <text x="16" y="22" text-anchor="middle" fill="white" font-size="18" font-family="sans-serif" font-weight="bold">AV</text>
</svg>`;
writeFileSync(join(outDir, 'favicon.svg'), favicon);

// Each entry: [index, search keywords] — keywords chosen to match the video title
const thumbnails = [
  [1,  'jazz,concert,stage'],
  [2,  'pasta,cooking,italian'],
  [3,  'soccer,football,tournament'],
  [4,  'watercolor,painting,art'],
  [5,  'python,programming,laptop'],
  [6,  'garden,spring,flowers'],
  [7,  'book,reading,library'],
  [8,  'acoustic,guitar,microphone'],
  [9,  'thai,food,cooking'],
  [10, 'basketball,court,game'],
  [11, 'oil,painting,landscape'],
  [12, 'web,development,code'],
  [13, 'rose,pruning,garden'],
  [14, 'science,fiction,books'],
  [15, 'blues,folk,music'],
  [16, 'pastry,baking,french'],
  [17, 'table,tennis,pingpong'],
  [18, 'digital,art,illustration'],
  [19, 'cloud,computing,server'],
  [20, 'compost,soil,garden'],
  [21, 'mystery,detective,book'],
  [22, 'piano,recital,concert'],
  [23, 'sushi,japanese,food'],
  [24, 'volleyball,beach,sport'],
  [25, 'pottery,ceramics,clay'],
  [26, 'artificial,intelligence,robot'],
  [27, 'herbs,garden,plants'],
  [28, 'classic,literature,novel'],
  [29, 'latin,dance,salsa'],
  [30, 'bread,baking,dough'],
  [31, 'badminton,racket,sport'],
  [32, 'sketch,drawing,pencil'],
  [33, 'cybersecurity,hacker,lock'],
  [34, 'winter,vegetables,growing'],
  [35, 'fantasy,tolkien,books'],
  [36, 'choir,singing,holiday'],
  [37, 'curry,indian,spices'],
  [38, 'running,marathon,race'],
  [39, 'photography,camera,walk'],
  [40, 'blockchain,crypto,technology'],
  [41, 'indoor,plants,houseplant'],
  [42, 'poetry,reading,writing'],
];

async function downloadImage(index, keywords) {
  const num = String(index).padStart(2, '0');
  const filePath = join(outDir, `thumb-${num}.jpg`);

  // loremflickr serves real Creative Commons photos matching keywords
  // lock parameter ensures deterministic results
  const url = `https://loremflickr.com/640/360/${keywords}?lock=${index}`;

  for (let attempt = 0; attempt < 3; attempt++) {
    try {
      const res = await fetch(url, { redirect: 'follow' });
      if (!res.ok) throw new Error(`HTTP ${res.status}`);
      const buffer = Buffer.from(await res.arrayBuffer());
      if (buffer.length < 1000) throw new Error('Image too small, likely error');
      writeFileSync(filePath, buffer);
      console.log(`  [${num}] OK (${(buffer.length / 1024).toFixed(0)} KB) — ${keywords}`);
      return;
    } catch (err) {
      if (attempt < 2) {
        console.log(`  [${num}] Retry ${attempt + 1}...`);
        await new Promise(r => setTimeout(r, 1000));
      } else {
        console.error(`  [${num}] FAILED: ${err.message}`);
      }
    }
  }
}

console.log('Downloading 42 topic-matched thumbnails from loremflickr.com...\n');

const BATCH = 4;
for (let i = 0; i < thumbnails.length; i += BATCH) {
  const batch = thumbnails.slice(i, i + BATCH);
  await Promise.all(batch.map(([idx, kw]) => downloadImage(idx, kw)));
}

console.log('\nDone! 42 topic-matched thumbnails in public/thumbnails/');